Relay having improved armature and mobile contact assembly



Sept. 26, 1967 c. T. ROESSLER ETAL 3,344,253

RELAY HAVING IMPROVED ARMATURE AND MOBILE CONTACT ASSEMBLY Filed Feb. 15, 1965 "-I-N-VE NI R. CLARK T- ROESSLER RONALD V TETZ United States Patent 3,344,253 RELAY HAVING IMPROVED ARMATURE AND MOBILE CONTACT ASSEMBLY Clark T. Roessler, San Jose, and Ronald V. Tetz, Los

Gatos, Calif., assignors to Jennings Radio Manufacturing Corporation, San Jose, Calif., a corporation of Delaware Filed Feb. 15,1965, Ser. No. 432,507 6 Claims. (Cl. 200-144) ABSTRACT OF THE DISCLOSURE In a relay, a mobile contact assembly is provided including a dielectric stem secured at one end on a displaceable armature and having partially supported on its other end a mobile contact formed by a hair-pin shaped resilient metallic strip. The ends of the two arms of the strip are bifurcated and loosely but interlockingly engage the bifurcated end of an associated fixed contact point. The dielectric stem is caught between the arms of the hair-pin shaped contact, and the folded-over end of the strip is loosely disposed between two adjacent fixed contact points. The armature is biased in a we determined direction by a U-shaped spring clip so that the mobile contact normally makes a circuit between one of the fixed contacts and the contact point on which the mobile contact is partially supported.

The invention relates to relays, and particularly to an armature and mobile contact assembly for an electromagnetically operated relay.

One of the objects of the invention is to simplify the construction of a vacuum relay and thereby reduce the cost to the ultimate consumer.

Another object of the invention is to provide an armature assembly for an electromagnetically operated relay in which the armature is mounted in a manner to reduce friction and the effects of vibration.

A still further object of the invention is to provide ,an armature assembly for an electromagnetically actuated relay in which the armature and mobile contact assembly is economical to fabricate and assemble, reliable, light in weight to reduce inertial effects and quickly responsive to a magnetic operating force.

Heretofore it has been the practice to utilize an armature construction in which the armature was pivotally hinged on ,a supporting member by interengaging lugs and a pivot pin. In addition, the mobile contact in association with this conventional type armature has usually provided a degree of flexibility which is undesirable in a relay of this type. Accordingly, it is another of the objects of this invention to provide a mobile contact and armature arrangement in which theflexibility in the system is built into the mobile contact assembly, with little or no flexibility in the remaining structure.

In conventional armature and mobile contact assemblies one of the disadvantages has been the existence of undesirable vibratory movement and therefore unreliable operation of the relay in environments where vibration is an important factor. Accordingly, it is a still further object of the invention to provide an armature and mobile contact assembly having substantially improved vibration characteristics.

The movement of the movable contact in a relay of this type is dependent upon the movement of the armature. It has been found that through continual movement -of the armature over a long period wear results in misalignment of the armature with a consequent impairment of the reliability and efliciency of the relay.

Therefore, it is a still further object of the invention to provide a vacuum relay in which the armature and mobile contact assembly have been designed to cooperate with one another to reduce the total travel of the armature so as to increase the efliciency of the relay.

In conventional relays where the armature isnormally pivoted on a pivotal pin-journaled on an appropriate support, the amount of friction which must be overcome by the magnetic system is substantial and must be compensated by an increase in the power expended to operate the relay. This friction also results in wear of the parts, which causes contamination of the interior of the envelope. It is therefore still another object of the invention to provide an armature assembly in which pivotal movement is accomplished with no friction involved.

The invention possesses other objects and features of advantage, some of which, with the foregoing, will be apparent from the following description and the drawings. It is to be understood however that the invention is not limited to the embodiment illustrated and described, as it may be embodied in various forms within the scope of the appended claims.

Referring to the drawings:

FIG. 1 is a vertical cross-sectional view through the longitudinal axis of the relay.

FIG. 2 is a horizontal cross-sectional view taken in the plane 2-2 of FIG. 1.

FIG. 3 is a fragmentary view in elevation illustrating the resilient nature of the mobile contact.

FIG. 4 is a fragmentary view partly in elevation and partly in section illustrating the relationship between the resilient mobile contact and one of the fixed contacts.

FIG. 5 is a fragmentary perspective view showing the relationship of the mounted armature, the actuator stem, and the spring and abutment plate assembly which resiliently retains the armature in position.

Briefly considered, the vacuum relay of the invention comprises a hermetically sealed envelope closed at one end by an end cap including a tubulation, and closed at the other end by an end cap on which is mounted an electromagnetic actuator assembly. The actuator assembly includes an armature pivotally positioned within the envelope and having in association therewith a mobile contact assembly movable to make or break a circuit through a plurality of spaced fixed contact points within the envelope on one of which the mobile contact is conductively mounted.

In terms of greater detail, the relay of the invention comprises an envelope portion 2, preferably fabricated from tubular ceramic, and closed at its upper end (as viewed in FIG. 1) by an end plate or cap 3, having a peripheral flange 4 hermetically bonded to the associated end of the ceramic member 2, and provided centrally with a tubulation 6, pinched off as shown to seal the envelope after evacuation thereof. The tubulation is provided with a protective cap 7 the interior of which between the protective cap and tubulation is filled with a cushioning material 8 such as silicone rubber.

A plurality of fixed contacts 9, 12 and 13 are provided Within the envelope arranged as shown best in FIG. 2, the inner ends of the contacts being circumferentially spaced about a central axis of the envelope, with each of the fixed contacts forming an integral part of a terminal lead supported on the dielectric portion 2 and extending outside of the envelope as shown.

The fixed contact 13 (FIG. 2) is provided with a slot 14 extending axially along the contact and terminal lead and in which slot are resiliently trapped the free end portions of the two spring arms 16 and 17 of mobile contact assembly 18, the arm 17 being formed with a transverse groove or depression 17 i The mobile contact assembly is engaged by a vertically extending dielectric stem 19, with the upper end of the stem lying in the groove 17 and resiliently held therein by the inherent resilience of the spring arms 16 and 17.

The lower end portion 21 of the dielectric stem is fixedly secured in an elongated box-like spring clip or bracket 22 brazed or otherwise secured at its lower end to an armature 23 and crimped as shown along opposite sides to provide inwardly extending portions adapted to impinge against the lower end of the stem. The relationship of the spring arms 16 and 17 of the mobile contact 18 with respect to the slot 14 formed in the fixed contact 13 is best shown in FIGS. 3 and 4 and will hereinafter be explained in greater detail.

As shown best in FIGS. 1 and 2, the armature 23 comprises a magnetically responsive plate extending transversely across the annular inwardly extending mounting portion 24 which is integral with the cylindrical mounting portion 27 of annular end plate or seal flange 28. The magnetic housing 25 is brazed within the cylindrical mounting portion 27 as shown. The end plate is provided with an outer peripheral edge portion 29 which is heliarc welded to the flange 31 which is in turn brazed or otherwise hermetically bonded to the associated end of the ceramic member 2.

The armature is pivotally supported in a substantially frictionless manner adjacent the inner surface of the flange 24 by an abutment plate 32, formed with a turned-up portion 33 as shown best in FIGS. 1 and 5, which forms a pocket within which is detachably secured or anchored one end of one leg of a U-shaped spring clip 34, the other leg 36 of which is provided with an angularly disposed portion 37 adapted to resiliently engage beneath a lug 38 formed adjacent one edge of the armature 23. As shown best in FIG. 5, the abutment plate 32 is provided with an appropriate notch 39 adapted to provide suflicient clearance for pivotal movement of the lug 38. It should be noted that the lug functions in the nature of a lever arm, and that the resilient spring clip 34 functions to impose a rotational moment on the armature plate 23 with its engagement with abutment plate 32 functioning as the fulcrum and defining the axis of rotation. It will thus be seen, as shown clearly in FIGS. 1 and 2, that the resilience of the spring clip 34 retains the mobile contact 18 in a make position with respect to the fixed contacts 12 and 13, whereas actuation of a coil 41 to energize the magnetic circuit, of which core member 42 and shell 25 form a part, will result in the stem 19 (as viewed in FIG. 1) moving transversely to the left so as to engage or make contacts 9 and 13, and disengage fixed contacts 12 and 13.

It will thus be seen that fabrication of the relay is greatly facilitated over conventional-type relays requiring physical bonding of the movable contact and actuator assembly to supporting structure within the evacuated envelope. In the present relay, for instance, the spring arms 16 and 17 of the mobile contact 18 are provided adjacent their free ends with a notch, as shown best in FIG. 4, defined by a pair of spaced ears 43 and adapted to straddle the associated slotted and fixed contact 13 so as to prevent vertical movement of the mobile contact with respect to the fixed contacts. This stabilization of the mobile contact is accomplished by the overlapping relationship of portions of the mobile contact and fixed contact, and this relationship also tends to stabilize the stem 19. On the other hand, at its other end, the stem is stabilized by virtue of the resilient pressure exerted on the armature by the spring clip 34.

It will thus be seen that apart from the mobile contact itself, there is little or no flexibility in the remainder of the assembly, thus increasing the reliability of the unit. Additionally, it will be apparent that whether the mobile contact is in the position indicated in the drawings, or

whether it is in the position which it would assume upon energization of the coil 41, the mobile contact will always be resiliently pressed against the fixed contacts which it bridges, thus reducing contact resistance and the efiects of shock and vibration. Also, it should be noted that the pressure exerted by the upper end of the stem against either arm 16 or 17 is in a direction to be borne only by one of such arms, and that such pressure does not tend to disengage the mobile contact from the slotted fixed contact on which it is supported.

We claim:

1. A relay comprising an hermetically sealed envelope closed at each opposite end, a plurality of spaced fixed contacts within the envelope integral with spaced terminal leads extending out of the envelope, a mobile contact condnctively mounted on one of the fixed contacts and selectively movable into or out of engagement with the other fixed contacts to make or break a circuit through the contact on which the movable contact is mounted and at least one of the other fixed contacts, said mobile contact comprising a resilient metallic strip doubled upon itself to provide a pair of juxtaposed spring arms biased away from each other, the free ends of the spring arms resiliently engaging the fixed contact on which the mobile contact is mounted, an actuator assembly mounted on one of the envelope ends and including an armature mounted within the envelope and normally pivotally biased resiliently in one direction and means outside the envelope selectively operable to pivot the armature in the other direction, and means interposed between the arm-ature and the mobile contact to effect movement of the mobile contact upon movement of the armature.

2. A relay comprising an hermetically sealed envelope closed at each opposite end, a plurality of spaced fixed contacts within the envelope integral with spaced terminal leads extending out of the envelope, one of said fixed contacts being bifurcated to form a slot, a mobile contact conductively mounted on said bifurcated fixed contact and selectively movable into or out of engagement with the other fixed contacts to make or break a circuit through the contact on which the movable contact is mounted and at least one of the other fixed contacts, said mobile contact being plate-like and formed with a slot along one side whereby when the mobile contact is mounted on the supporting fixed contact the bifurcated end of the fixed contact overlaps a portion of the mobile contact and a portion of the mobile contact overlaps the supporting fixed contact, an actuator assembly mounted on one of the envelope ends and including an armature mounted within the envelope and normally pivotally biased resiliently in one direction and means outside the envelope selectively operable to pivot the armature in the other direction, and means interposed between the armature and the mobile contact to effect movement of the mobile contact upon movement of the armature.

3. The combination according to claim 1, in which the means interposed between the armature and mobile contact to effect movement of the mobile contact comprises a dielectric stem one end of which is caught and resiliently retained between said spring arms of the mobile contact when the free ends thereof are biased toward each other to resiliently engage the associated supporting fixed contact.

4. A relay comprising an hermetically sealed envelope closed at each opposite end, a plurality of spaced fixed contacts within the envelope integral with spaced terminal leads extending out of the envelope, a mobile contact conductively mounted on one of the fixed contacts and selectively movable into or out of engagement with the other fixed contacts to make or break a circuit through the contact on which the movable contact is mounted and at least one of the other fixed contacts, an actuator assembly mounted on one of the envelope ends and including an armature mounted within the envelope and normally pivotally biased resiliently in one direction and means outside the envelope selectively operable to pivot the armature in the other direction, a dielectric stem secured at one end to the armature and engaging the mobile contact a at its other end, and means for securing said one end of the stem to the armature comprising an elongated boxlike bracket fixed by one of its ends to the armature, said dielectric stern extending into the bracket and the sides of the bracket being crimped to provide inwardly extending portions impinging against the stem to lock the stem to the armature.

5. In a relay, an abutment plate, an armature abutting said abutment plate and responsive to a magnetic circuit to pivot the armature in one direction, a lug on the armature adjacent the edge thereof abutting the abutment plate, said abutment plate forming the fulcrum for pivotal movement of the armature, and a spring clip resiliently interposed between the abutment plate and the end of the lug remote from the armature whereby said lug functions as a lever to pivot the armature on the edge of the abutment plate.

References Cited UNITED STATES PATENTS 2,423,116 7/1947 Price 335-203 X 2,834,847 7/1958 Jennings 335-154 2,886,668 5/1959 Steward et al 200-144 X 2,912,539 11/1959 Jennings 335-154 3,154,655 10/ 1964 Hawkins 200144 3,238,324 3/1966 Roessler 335-154 X 3,239,727 3/1966 Zupa 335-276 X 3,250,886 5/1966 De Lucia et al. 335-151 X ROBERT S. MACON, Primary Examiner. 

1. A RELAY COMPRISING AN HERMETICALLY SEALED ENVELOPE CLOSED AT EACH OPPOSITE END, A PLURALITY OF SPACED FIXED CONTACTS WITHIN THE ENVELOPE INTEGRAL WITH SPACED TERMINAL LEADS EXTENDING OUT OF THE ENVELOPE, A MOBILE CONTACT CONDUCTIVELY MOUNTED ON ONE OF THE FIXED CONTACTS AND SELECTIVELY MOVABLE INTO OR OUT OF ENGAGEMENT WITH THE OTHER FIXED CONTACTS TO MAKE OR BREAK A CIRCUIT THROUGH THE CONTACT ON WHICH THE MOVABLE CONTACT IS MOUNTED AND AT LEAST ONE OF THE OTHER FIXED CONTACTS, SAID MOBILE CONTACT COMPRISING A RESILIENT METALLIC STRIP DOUBLE UPON ITSELF TO PROVIDE A PAIR OF JUXTAPOSED SPRING ARMS BIASED AWAY FROM EACH OTHER, THE FREE ENDS OF THE SPRING ARMS RESILIENTLY ENGAGING THE FIXED CONTACT ON WHICH THE MOBILE CONTACT IS MOUNTED, AN ACTUATOR ASSEMBLY MOUNTED ON ONE OF THE ENVELOPE ENDS AND INCLUDING A ARMATURE MOUNTED WITHIN THE ENVELOPE AND NORMALLY PIVOTALLY BIASED RESILIENTLY IN ONE DIRECTION AND MEANS OUTSIDE THE ENVELOPE SELECTIVELY OPERABLE TO PIVOT THE ARMATURE IN THE OTHER DIRECTION, AND MEANS INTERPOSED BETWEEN THE ARMATURE AND THE MOBILE CONTACT TO EFFECT MOVEMENT OF THE MOBILE CONTACT UPON MOVEMENT OF THE ARMATURE. 